Every time I have sold URC on eBay the buyer complains about something trying to get money off or trying to screw me.  Had a listing a while back for a MX850 that had a broken RF antenna but IR worked fine.  This was stated in the listing.  Guy sniped it at the last second.  He received it and claimed I didn't sent him what the auction stated because the FCC ID said MX700.  I explained what that was and his complaint is that the remote is not an RF remote, based on that.  When I said all black remotes in that style were 850s and RF, this one simply had a broken antenna as stated in the auction, he sent links to B&K reshelled remotes that are IR only.  I had to go through ebay and told him to contact URC with the serial number if he didn't believe me.  Took months to get paid the measly money the remote brought in.